Electrical connection



p 1, 1964 w. GLUCK ELECTRICAL CONNECTION 3 Sheets-Sheet 1 Filed May 19,1960 FIG. 2

FIG. I

FIG. 5"

I FIG.6

INVENTOR. WILLIAM GLUCK ATTORNEYS Sept. 1, 1964 w. GLUCK 3,147,059

ELECTRICAL CONNECTION Filed May 19, 1960 3 Sheets-Sheet 2 42 \IIIIIIIIIIIIT!IIII FIG.8

IN VEN TOR.

WILLIAM GLUCK ATTOR N EYS Sept. 1, 1964 w. GLUCK 3,147,059

ELECTRICAL CONNECTION Filed May 19, 1960 3 Sheets-Sheet 3 JNVENTOR. FIG.|3 WILLIAM GLUCK ATTORNEYS United States Patent 3,147,059 ELECTRICALCONNECTIGN William Gluck, Waltham, Mass., assignor to UnitedInternational Dynamics ,Corp., Boston, Mass, a corporation ofMassachusetts Filed May 19, 1960, Ser. No. 30,162 6 Claims. (Cl. 339193)The present invention relates in general to removably establishingelectrical connection and more particularly concerns sockets forreceiving electrical components and the novel contacts comprising thesockets. The novel sockets are sturdy, compact and adaptable forautomatic insertion into printed circuit boards. The pins connected toan external component may be easily inserted into and removed from thenovel socket contacts, yet positive and firm electrical and mechanicalcontact is assured for many insertions and withdrawals.

A typical prior art miniature tube socket comprises contacts ofconducting material having a generally U- shaped cross-section with thelegs of the U pointing inward to resiliently grip an inserted conductingpin inserted into the contact. These sockets have a number ofdisadvantages. Tube pins and socket contacts must be in nearly perfectalignment. Great pressure is often necessary to insert a tube into thesocket when the socket is new. As a result, it is not uncommon to bendone or more tube pins during an initial attempt at insertion. Thisintroduces annoying and costly delays because the pin must bestraightened before the tube can be inserted into the socket. Inaddition, bending weakens the pin and may cause strains in associatedstructure. After a number of insertions and withdrawals have been madein a particular socket, a tube may be inserted more easily, but theestablishment of electrical contact is not infrequently unreliable sothat defective performance of an associated circuit is due to poorcontact between the pin and socket contact. The disadvantages of poorcontact are obvious.

The disadvantages enumerated above are serious enough for conventionalsockets secured to a chassis by rivets or screws and nuts. However,sockets using such contacts and adapted for automatic insertion intoprinted circuit boards are complex structures. These structurestypically comprise a pair of spaced parallel supporting bases which arereservoirs for socket-deteriorating moisture accumulation, theaccumulated moisture also reducing the resistance between contacts. Thelarge number of parts in such sockets adds to the cost and complexity ofmanufacture.

Accordingly, it is an important object of the present invention toprovide a socket for establishing electrical connection to a removeablecircuit component which freely admits and releases the component whendesired but snugly engages each contact pin of the component when thecomponent rests in the socket.

It is an object of the invention to provide a socket in accordance withthe preceding object of simple compact form which is relatively easy tofabricate, low in cost and yet retains the desired properties for anexceptionally large number of withdrawals and insertions.

3,147,059 Fatented Sept. 1, 1964 a with opposed ears extending outwardfrom and generally It is still another object of the invention toprovide a A perpendicular to the first portion legs. These ears arepreferably in intimate contact with one side of the supporting basewhile the other side of the base is in intimate contact with an adjacentedge of the second portion to restrict relative movement between thecontact and the base.

In one form of the socket, the openings are spaced along a line, spacebeing conserved by arranging the length of at least one opening tointersect that line and a line collinear with the length of the adjacentopening. Preferably, the lengths of alternate openings are generallyparallel.

Each contact is preferably formed from a generally T-shaped sheet ofconductive material preferably formed with an opening substantiallyalong the axis of symmetry of the stern portion of the T just above theboundary between the stem portion and the cap portion of the T. The capportion includes two pairs of slits. A first pair of slits extendsperpendicular to and from that edge of the cap portion substantiallycollinear with said boundary. A second pair of slits extendsperpendicular to and inwardly of respective ones of the first pair ofslits.

Numerous other features, objects and advantages of the invention willbecome apparent from the following specification when read in connectionwith the accompanying drawing in which:

FIGS. 1 and 2 are side and front views respectively of one embodiment ofa contact according to the invention;

FIGS. 3 and 4 are side and front views respectively of anotherembodiment;

FIGS. 5 and 6 show blanks from which the abovementioned contacts areformed;

FIG. 7 is a perspective view of a tube socket according to theinvention;

FIG. 8 shows a view of the novel tube socket inserted into a printedcircuit board;

FIG. 9 shows a top view of a printed circuit board with openingsarranged to accommodate the novel socket of FIG. 7;

FIG. 10 is a top View of a novel transistor socket according to theinvention;

FIG. 11 is a sectional view through section 9-9 of FIG. 8;

FIG. 12 is a top view of a socket suitable for receiving a replaceablecomponent having seven coplanar pins; and

FIG. 13 is a side view of the structure shown in FIG. 12.

With reference now to the drawing and more particularly FIGS. 1 and 2thereof, there is shown a representative embodiment of a contactaccording to the invention. The contact is made of conducting materialhaving a lower portion 11 and upper portion 12 generally separated by anopening 13 and both being of generally U-shaped cross section. Anopening 13 is formed along a part of the boundary between the upper andlower portions.

The upper portion 12 is formed with a pair of downwardly extendingopposed legs 14 and 15 extending into the volume bounded by extensionsof the sides of the upper portion 12. The legs 14 and 15 are formed withcurved ends that have convex surfaces resiliently urged together innormal tangential contact along the vertical longitudinal 3 axis commonto the upper portion 12 and lower portion 11. The legs are cantileversbendable about respective axes that are generally perpendicular to thevertical longitudinal axis, the said axes being spaced from the curvedends by straight portions of the respective legs.

The upper portion 12 is also formed with ears 21 and 22 extendingoutward from and generally perpendicular to legs 14 and 15,respectively. The ears 21 and 22 coact with the upper edges 23 and 24,respectively, of sidewalls 16 and 17, respectively, for snugly engagingopposite sides of an insulating supporting base containing the contacts.

Sidewalls 16 and 17 are formed with slots 25 and 26, respectively. Thehorizontal edges 27 and 23 adjacent to slots 25 and 26, respectively,are adapted to rest upon the top surface of a printed circuit board. Thedownwardly sloping edges 31 and 32 adjacent to slots 25 and 26,respectively, allow the contact to seat properly in printed circuitboards of different thicknesses. The downwardly sloping edges 33 and 34function to guide the contact through the opening in the printed circuitboard when the socket is initially inserted.

Referring to FIG. 5, there is shown a blank suitable for being formedinto the contact shown in FIGS. 1 and 2. The same reference numeralsidentify corresponding portions in FIGS. 1, 2 and 5. The blank isgenerally T- shaped as shown and made of Phosphor bronze or othersuitable conducting material having some resilience.

The upper and lower portions 12 and 11 comprise the cap and stem,respectively, of the T. The cap portion is formed with vertical slits 35and 36 extending from and generally perpendicular to the lower edges oflegs 14 and 15, respectively, these edges being extensions of theboundary between the cap and stem of the T. The upper edges 23 and 24 ofsidewalls 16 and 17, respectively, appear as slits extending inwardlyfrom and generally perpendicular to the vertical slits 35 and 36,respectively. By the use of suitable punches and dies, the blank is bentabout its vertical axis of symmetry so that the sidewalls 16 and 17 andthe legs 14 and 15 are opposed, the bottom portions of legs 14 and 15being crimped together while cars 21 and 22 are bent over so that thestructure appears as shown in FIG. 2. The corners near edges 27 and 28may be bent inwardly slightly. The corners at edges 23 and 24 may bebent outward slightly to provide a better gripping means for engagingthe lower surface of the insulating base. The opening 13, while notessential, facilitates bending sidewalls into opposed generally parallelrelationship because the depending legs obstruct the volume where aprojection on a punch might otherwise be inserted and function as afulcrum during bending.

Referring to FIGS. 3 and 4-, there is shown side and front views,respectively, of another embodiment of a contact according to theinvention. Since the structure of this contact is similar in principleto the structure of the contact described above in connection with FIGS.1, 2 and 5, portions of the former contact which correspond to por tionsof the latter contact are designated by the same reference numeral withan appended prime. The description above is applicable to the contactsin FIGS. 3 and 4 by considering reference to portions in FIGS. l-2 asreferring to the portions designated by the same reference numeralprimed in FIGS. 3-4.

The contact shown in FIGS. 3-4 is formed with the lower portion 11'being curved away from the upper portion 12'. This is advantageous incertain applications where it is desired to have a socket with bottomconnection points which pass through the printed circuit board separatedby a greater distance than the pin connections of the componentsupported in the socket.

For example, a perspective view of such a socket is shown in FIG. 7 foruse in supporting a nine pin miniature tube. The socket of FIG. 7 isshown in position in a printed circuit board in FIG. 8. The arrangementof openings in the printed circuit board as shown in FIG. 9

are spaced to accommodate either a prior art tube socket, or the noveltube socket shown in FIG. 7.

The structure in FIGS. 3 and 4 also includes a small tab 41. The purposeof tab 41 is to hold the socket in the printed circuit board prior tosoldering. Tab 41 effects a snap action when the socket is inserted intothe printed circuit chassis. The printed circuit chassis with theinserted socket is then usually dip soldered.

Another feature of the contact of FIG. 3 resides in the horizontal edges27' and 28'. While the contact of FIG. 1 is satisfactory for manypurposes, pressing such contacts through a punched hole in an insulatingsupporting base will sometimes result in an unsatisfactory socket if theedges of the hole punched in the base are rough. The sharp edges 27 and28, bent inward to facilitate slipping through the hole in the base,sometimes scrape and chip rough-edged holes, especially since the burron the stamped contact is on the outside.

This problem is materially reduced with the contact of FIG. 3 becausethe horizontal edges 27' and 28' pass through the hole in the base at anangle which prevents cutting engagement with the edges of the hole asthese edges follow the lead of the smooth curved surface of lowerportion 11' during insertion.

This blank shown in FIG. 6 may be bent to form the contact of P165. 3and 4 in a manner similar to the bending operation described above withthe exception that the curving of the lower portion 11 is alsoaccomplished during the bending operation.

Referring to FIG. 7, there is shown a nine pin miniature socket in whichnine of the contacts of the type shown in FIGS. 3 and 4 are arrangedabout a circle in an insulating supporting base 42 having a centralopening 44 and a keying slot 45. The contacts 43 drop into matingopenings 46, shown in FIG. 9, in a printed circuit board 47.

Details of a contact 43 resting in the printed circuit board are shownin the cutaway view of FIG. 8. The edge 28 rests upon the top surface ofthe printed circuit board 47 and the intersection of edges 32' and 34bears against the inner surface of the opening 46 while tab 41 snaps outto grip the under surface of board 47 to insure a tight mechanical fit.FIG. 8 also shows the insulating supporting base 42 intimately contactedby an ear such as ear 22 on the top surface and by the upper edge 24' oflower portion 12 at its bottom surface.

Referring to FIGS. 10 and 11, there are shown a top view and a sidesectional view, respectively, of a novel socket according to theinvention especially suitable as a transistor socket. The contacts 51-53are shown mounted in an insulating support base 54 accommodating pins55-57, respectively, of a transistor. Pins 55-57 are aligned along astraight line which coincides with the length of the openingaccommodating contacts 51 and 53 while being perpendicular to the lengthof the opening which accommodates contact 52.

Referring to FIG. 12, there is shown a socket capable of accommodating areplaceable circuit component which might comprise an interstagecoupling network and have seven pins aligned along a straight line 61which passes through the urged-together upper portion contact legs 14and 15' of each contact 62, the contacts 62 being accommodated inopenings in an insulating supporting base 63. The length of each ofthese openings makes an angle of approximately 45 with the line 61 andapproximately with the length of adjacent openings, alternate openingsbeing substantially parallel to one another. This is an advantageousarrangement because the differently oriented contacts '62 form a compactarrangement with the spaced rows of legs providing a firm support forthe socket upon a printed circuit board.

There has been described novel sockets and contacts which are low incost, relatively easy to fabricate, compact, and suitable for automaticinsertion into printed circuit boards. Replaceable components may beeasily inserted into and withdrawn from the sockets but are firmly heldin place to continuously provide good conductive contact despitenumerous removals and withdrawals of components.

The specific embodiments described herein are by way of example only. Itis evident that those skilled in the art may now make numerousmodifications of and departure from the specific embodiments andtechniques described herein without departing from the inventiveconcepts. Consequently, the invention is to be construed as limited onlyby the spirit and scope of the appended claims.

What is claimed is:

1. A socket comprising,

a supporting insulating base consisting of a disc of uniform thicknessformed with a plurality of openings each being of uniform cross sectionand snugly accommodating an electrical contact for establishing aconductive path between said contact and an insertable conductor,

each of said contacts comprising,

a structure of conducting material having a first portion of generallyU-shaped cross section and a second portion connected to said firstportion and also of generally U-shaped cross section,

said first and second portions being spaced along a common longitudinalaxis generally perpendicular to said disc,

said first portion having a pair of opposed legs formed with curved endsthat have convex surfaces resiliently urged toward normal tangentialcontact along said common longitudinal axis whereby said legs may beurged apart when said insertable conductor is forced therebetween alongsaid common axis to snugly accommodate the latter and establishconductive contact therewith,

said legs being cantilevers bendable about respective axes in said firstportion generally perpendicular to said common longitudinal axis andgenerally parallel to said disc,

said axes being spaced from said curved ends by straight portions of therespective legs,

said curved ends and the lower sections of said straight portionsextending outside the thickness dimension of said disc and beingdisposed below the underside of said disc,

the sole means for supporting each of said contacts in said base beingthe portion of said base immediately adjacent to a respective opening.

2. A socket in accordance with claim 1 wherein said first portion ofeach contact is formed with opposed ears extending outward from andgenerally perpendicular to said legs,

said ears being in intimate contact with one side of said supportingbase,

a part of the end of said second portion near said first portion beingin intimate contact with the other side of said supporting base torestrict relative movement between each contact and said base.

3. A contact in accordance with claim 1 wherein said first portion isformed with opposed ears extending outward from and generallyperpendicular to said legs.

4. A socket in accordance with claim 1 wherein said openings are spacedalong a circle.

5. A socket in accordance with claim 1 wherein said openings areclosely-spaced along a line, each opening having a length greater thanits width, the length of at least one opening intersecting said line anda line collinear with the length of the adjacent opening.

6. A socket in accordance with claim 5 wherein the lengths of alternateones of said openings are substantially parallel.

References Cited in the file of this patent UNITED STATES PATENTS1,671,226 Caruso May 29, 1928 2,304,808 Draving Dec. 15, 1942 2,458,097Penfold Jan. 4, 1949 2,480,059 Stickney Aug. 23, 1949 2,482,990 OlsonSept. 27, 1949 2,602,988 Klym July 15, 1952 2,683,259 Lowther July 6,1954 2,745,081 Ofrerman May 8, 1956 2,747,169 Johanson May 22, 19562,793,353 Del Camp May 21, 1957 2,793,354 Heimbach May 21, 19572,817,067 Paradise Dec. 17, 1957 2,825,881 Del Camp Mar. 4, 19582,857,582 Wintriss Oct. 21, 1958 2,861,253 Johanson Nov. 18, 19582,908,885 Deakin Oct. 13, 1959 2,972,727 Flanagan et a1 Feb. 21, 1961FOREIGN PATENTS 776,881 Great Britain June 12, 1957

1. A SOCKET COMPRISING, A SUPPORTING INSULATING BASE CONSISTING OF A DISC OF UNIFORM THICKNESS FORMED WITH A PLURALITY OF OPENINGS EACH BEING OF UNIFORM CROSS SECTION AND SNUGLY ACCOMMODATING AN ELECTRICAL CONTACT FOR ESTABLISHING A CONDUCTIVE PATH BETWEEN SAID CONTACT AND AN INSERTABLE CONDUCTOR, EACH OF SAID CONTACTS COMPRISING, A STRUCTURE OF CONDUCTING MATERIAL HAVING A FIRST PORTION OF GENERALLY U-SHAPED CROSS SECTION AND A SECOND PORTION CONNECTED TO SAID FIRST PORTION AND ALSO OF GENERALLY U-SHAPED CROSS SECTION, SAID FIRST AND SECOND PORTIONS BEING SPACED ALONG A COMMON LONGITUDINAL AXIS GENERALLY PERPENDICULAR TO SAID DISC, SAID FIRST PORTION HAVING A PAIR OF OPPOSED LEGS FORMED WITH CURVED ENDS THAT HAVE CONVEX SURFACES RESILIENTLY URGED TOWARD NORMAL TANGENTIAL CONTACT ALONG SAID COMMON LONGITUDINAL AXIS WHEREBY SAID LEGS MAY BE URGED APART WHEN SAID INSERTABLE CONDUCTOR IS FORCED THEREBETWEEN ALONG SAID COMMON AXIS TO SNUGLY ACCOMMODATE THE LATTER AND ESTABLISH CONDUCTIVE CONTACT THEREWITH, SAID LEGS BEING CANTILEVERS BENDABLE ABOUT RESPECTIVE AXES IN SAID FIRST PORTION GENERALLY PERPENDICULAR TO SAID COMMON LONGITUDINAL AXIS AND GENERALLY PARALLEL TO SAID DISC, SAID AXES BEING SPACED FROM SAID CURVED ENDS BY STRAIGHT PORTIONS OF THE RESPECTIVE LEGS, SAID CURVED ENDS AND THE LOWER SECTIONS OF SAID STRAIGHT PORTIONS EXTENDING OUTSIDE THE THICKNESS DIMENSION OF SAID DISC AND BEING DISPOSED BELOW THE UNDERSIDE OF SAID DISC, THE SOLE MEANS FOR SUPPORTING EACH OF SAID CONTACTS IN SAID BASE BEING THE PORTION OF SAID BASE IMMEDIATELY ADJACENT TO A RESPECTIVE OPENING. 